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Modern Fair-Weather And Storm Sediment Transport Around Ship Island, Mississippi: Implications For Coastal Habitats And Restoration Efforts, Eve Rettew Eisemann

Master's Theses

The Mississippi – Alabama barrier island chain is experiencing accelerated sea level rise, decreased sediment supply, and frequent hurricane impacts. These three factors drive unprecedented rates of morphology change and ecosystem reduction. All islands in the chain have experienced land loss on the order of hectares per year since records began in the 1840s. In 1969, Hurricane Camille impacted as a Category 5, breaching Ship Island, and significantly reduced viable seagrass habitat. Hurricane Katrina impacted as a Category 3 in 2005, further widening Camille Cut. To better understand the sustainability of these important islands and the ecosystems they support, sediment …

Bloom Or Bust: Retrospective Analysis Of The Giant Jellyfish, Nemopilema Nomurai (Scyphozoa: Rhizostomeae), Ecology In The East Asian Marginal Seas, Naomi Yoder

Master's Theses

The Giant Jellyfish, Nemopilema nomurai, is a large-bodied bloom-forming jellyfish that occurs in the semi-enclosed basins of the East Asian Marginal Seas. N. nomurai has bloomed more frequently in the past 20 years than in any period previously recorded. In Japan, recent N. nomurai blooms were responsible for millions of dollars in lost revenue and equipment damage to commercial fisheries alone. This study statistically analyzed 21 environmental factors in connection with N. nomurai occurrence (using occurrence as a proxy for blooms). Eight factors resulted in a statistically significant or marginally significant (p ≤ 0.10), linear or non-linear relationship with …

Structure-Property Relationships Of Polyisobutylene-Block-Polyamide Thermoplastic Elastomers, Morgan Dunn Heskett

Master's Theses

Thermoplastic elastomers (TPEs) are a class of polymer fit for a wide variety of applications due to their customizability. In the synthesis of these types of materials, an elastically-performing polymer, deemed the “soft block,” is combined with a stiffer “hard block” polymer, each of which can be selected based on their own specific properties in order to achieve desired material behavior in the final copolymer. Recently, the use of polyisobutylene as a soft block in combination with a polyamide hard block has been investigated for use in TPE synthesis. While the material showed some promising behavior, many properties were still …

Sedimentology Of A Small Estuarine Marsh Along East (Pensacola) Bay, Florida, Jesse Pfadenhauer

Honors Theses

Sediment samples from a marsh along East (Pensacola) Bay were analyzed using various laboratory techniques. The color, magnetic susceptibility, organic content, carbonate content, and sediment size distribution of each sample was measured to attain an overall profile of the sedimentary characteristics of the area. Using the GPS coordinates of each collection site, samples were categorized into sub-environments based on their position within the marsh. The trends within the study area and sub-environments were evaluated and interpreted. The data indicate that this marsh is a siliciclastic, fining-inland area that is frequently inundated with tidal fluctuations and storm surges. These storm surges …

Fast Method Of Particular Solutions For Solving Partial Differential Equations, Anup Raja Lamichhane

Dissertations

Method of particular solutions (MPS) has been implemented in many science and engineering problems but obtaining the closed-form particular solutions, the selection of the good shape parameter for various radial basis functions (RBFs) and simulation of the large-scale problems are some of the challenges which need to overcome. In this dissertation, we have used several techniques to overcome such challenges.

The closed-form particular solutions for the Matérn and Gaussian RBFs were not known yet. With the help of the symbolic computational tools, we have derived the closed-form particular solutions of the Matérn and Gaussian RBFs for the Laplace and biharmonic …

Design And Synthesis Of Dynamic Covalent Polymer Scaffolds With Controlled Architectures, Emily Annette Hoff

Dissertations

The design and synthesis of functional, controlled polymer architectures is essential to the development of new materials with precise and tailorable properties or applications. The work described in this dissertation focuses on the development of controlled polymer architectures with dynamic linkages for the design of multifunctional materials and surfaces via robust, efficient, and stimuli-responsive strategies.

In Chapter III, a post-polymerization modification strategy based on ambient temperature nucleophilic chemical deblocking of polymer scaffolds bearing N-heterocycle blocked isocyanate moieties is reported. Room temperature RAFT polymerization of three azole-N-carboxamide methacrylates, including 3,5-dimethyl pyrazole, imidazole, and 1,2,4-triazole derivatives, afforded reactive polymer scaffolds …

Electrogenerated Chemiluminescence Study Of Semiconductor Nanoparticles Towards Sensitive Detection Of Biomolecules, Yiliyasi Wusimanjiang

Dissertations

The main focus of this dissertation is to unfold the fundamental aspects of electrogenerated chemiluminescence (ECL) generation from semiconductor nanoparticles (also known as quantum dots or QDs) within different ECL systems. The ECL and photo-physical interactions between the CdTe QDs (λ_emission= ~760 nm) and the CdSe QDs (λ_emission= ~550 nm), as well as the effects of carbon nanotubes on ECL of QDs were separately investigated. Optimum experimental conditions for peptide bond formation on an electrode surface through EDC (1-ethyl-3-(-3-dimethylaminopropyl) carbodiimide hydrochloride)/NHS (N-Hydroxysulfosuccinimide) coupling were also revealed using cyclic voltammetry technique. Based on the information …

Cavity Ringdown Spectroscopy In Nitrogen/Oxygen Mixtures In The Presence Of Alpha Radiation, Sidney John Gautrau

Master's Theses

This research was part of an effort to experimentally validate computational models under development for radiation-induced atmospheric effects. Cavity Ringdown Spectroscopy (CRDS) was used to measure the concentration of chemical products generated as a result of radiation interactions in a controlled atmosphere. Experiments were conducted in a vacuum chamber interfaced with a gas introduction system that controlled the initial atmospheric composition. A quadrupole mass spectrometer and tunable dye laser were integrated to confirm initial atmospheric composition, and provide wavelength flexibility for detecting a variety of chemical products generated by radiation interactions. CRDS measurements were made for ozone production resulting from …

Determining The Viability Of Recent Storms As Modern Analogues For North-Central Gulf Of Mexico Paleotempestology Through Sedimentary Analysis And Storm Surge Reconstruction, Joshua Caleb Bregy

Master's Theses

The northern Gulf of Mexico has been devastated by recent intense storms. Camille (1969) and Katrina (2005) are two notable hurricanes that made landfall in virtually the same location in Mississippi. However, fully understanding the risks and processes associated with hurricane impacts is impeded by a short and fragmented instrumental record. Paleotempestology could potentially use modern analogues from intense storms in this region to extend the hurricane record back to pre-observational time. Existing empirically based models can back-calculate surge heights over coastal systems as a function of transport distance, particle settling velocity, and gravitational acceleration. We collected cores in a …

Correlation Of Polymer Performance And Hansen Solubility Parameters, Daniel Jobse Mania

Master's Theses

Ready-to-use (RTU) grout is becoming more important to the finish and remodeling construction industry. Market research shows it is a fast-growing product that not only is creating its own space, but is beginning to supplant existing technology.

The original intent of this research was to investigate formulation parameters and how they affect grout performance. It was learned that particle size and oil absorption (OA) value are important filler properties that affect performance as much as adequate packing density and optimal pigment volume concentration (PVC) without going beyond critical PVC (CPVC).

Polymer architecture was also determined to be extremely important, but …

Krylov Subspace Spectral Method With Multigrid For A Time-Dependent, Variable-Coefficient Partial Differential Equation, Haley Renee Dozier

Master's Theses

Krylov Subspace Spectral (KSS) methods are traditionally used to solve time-dependent, variable-coefficient PDEs. They are high-order accurate, component-wise methods that are efficient with variable input sizes.

This thesis will demonstrate how one can make KSS methods even more efficient by using a Multigrid-like approach for low-frequency components. The essential ingredients of Multigrid, such as restriction, residual correction, and prolongation, are adapted to the timedependent case. Then a comparison of KSS, KSS with Multigrid, KSS-EPI and standard Krylov projection methods will be demonstrated.

Protein Residue-Residue Contact Prediction Using Stacked Denoising Autoencoders, Joseph Bailey Luttrell Iv

Honors Theses

Protein residue-residue contact prediction is one of many areas of bioinformatics research that aims to assist researchers in the discovery of structural features of proteins. Predicting the existence of such structural features can provide a starting point for studying the tertiary structures of proteins. This has the potential to be useful in applications such as drug design where tertiary structure predictions may play an important role in approximating the interactions between drugs and their targets without expending the monetary resources necessary for preliminary experimentation. Here, four different methods involving deep learning, support vector machines (SVMs), and direct coupling analysis were …

The Influence Of The Electric Supply Industry On Economic Growth In Less Developed Countries, Edward Richard Bee

Dissertations

This study measures the impact that electrical outages have on manufacturing production in 135 less developed countries using stochastic frontier analysis and data from World Bank’s Investment Climate surveys. Outages of electricity, for firms with and without backup power sources, are the most frequently cited constraint on manufacturing growth in these surveys.

Outages are shown to reduce output below the production frontier by almost five percent in Africa and by a lower percentage in South Asia, Southeast Asia and the Middle East and North Africa. Production response to outages is quadratic in form. Outages also increase labor cost, reduce exports …

Hybrid Chebyshev Polynomial Scheme For The Numerical Solution Of Partial Differential Equations, Balaram Khatri Ghimire

Dissertations

In the numerical solution of partial differential equations (PDEs), it is common to find situations where the best choice is to use more than one method to arrive at an accurate solution. In this dissertation, hybrid Chebyshev polynomial scheme (HCPS) is proposed which is applied in two-step approach and one-step approach. In the two-step approach, first, Chebyshev polynomials are used to approximate a particular solution of a PDE. Chebyshev nodes which are the roots of Chebyshev polynomials are used in the polynomial interpolation due to its spectral convergence. Then, the resulting homogeneous equation is solved by boundary type methods including …

The Synthesis Of Chemosensors For Toxic Analytes, Johnathan Hugh Broome

Dissertations

A number of chemosensors have been designed and synthesized to target cations (Zn²⁺ions), neutral molecules (cathinones), charged molecules (aminoindanes), and anions. The Zn²⁺ ion sensor featured bistriazole designed binding unit and ferrocene signaling units. Characterization of Zn²⁺ ion binding was carried out with electrochemical techniques (CV and DPV), ¹H-NMR, mass spectrometry, and molecular modelling. It exhibited a 1:1 binding stoichiometry with Zn²⁺ and had an affinity for ZnCl₂ (Log K_1:1 = 4.1 ± 0.02) over other Zn²⁺ salts.

The cathinone probe was designed to selectively bind mephedrone over common street drugs …

Preparation And Characterization Of Singlet-Oxygen Generating Thiol-Ene Networks Containing Fullerene And Metallofullerene Derivatives, Emily Matthews Barker

Dissertations

This work explores the derivatization of C₆₀ and Sc₃N@C₈₀ with S-, P-, and C- centered radicals, and is the first exploration into the functionalization of Sc₃N@C₈₀ with sulfur and phosphorous. The number of addends bound to C₆₀, as a function of reaction time and molar ratios, as well as, structure-property relationships including thermal stability, solubility, and singlet oxygen generation were explored. Fullerene derivatives exhibiting enhanced solubility were incorporated into two different thiol-ene polymer matrices at varying thiol-ene monomer concentrations (1:1 or 1:0.75 molar equivalents) and at different C₆₀ loadings (0, …

A Library Of Coumarin-Enaminone Chemodosimeters For The Detection Of Analytes, Aaron Berrell Davis

Dissertations

Many anions and metal ions are of biological and environmental importance. This work describes our attempts to synthesize molecular probes to specifically target cyanide, zinc, cadmium and mercury as these species can often result in negative effects to the environment and the human body.

The work in this dissertation, describes the synthesis of a family of coumarin-enamine chemodosimeters, in a straightforward synthetic procedure, the reaction between 7-(diethylamino)-4-hydroxycoumarin and a primary amine. The work presented in this dissertation demonstrates that these molecules can play dual roles and therefore the work is split into two distinct parts: Part 1 describes one role …

Analysis Of The Intricacies Of Substrate Recognition Of High Mobility Group Proteins And Aminoacyl-Trna Synthetases Using Non-Cognate Substrates, Douglas Van Iverson Ii

Dissertations

The studies presented in section 1 (Chapters I-IV) focus on the design and development of nucleic acid four-way junctions (4WJs) to target a member of the high mobility group (HMG) proteins, the proinflammatory cytokine high mobility group box 1 protein (HMGB1). In the present study, hybrid PNA-DNA 4WJs based on a model DNA 4WJ were constructed to improve the thermal stability of 4WJs while maintaining strong binding affinity toward HMGB1. An electrophoretic mobility shift assay (EMSA) was used to examine the binding affinity of an isolated DNA binding domain of HMGB1, the HMGB1 b-box (HMGB1b), toward a set of PNA-DNA …

Automated Data Acquisition Of Deet Time-Dependent Concentration Profiles, Ryan D. Coleman

Honors Theses

Spatial insect repellents must maintain a sufficient concentration in the vapor phase to successfully deter pests. However, little is known regarding correlation of concentration to efficacy nor does there exist a standard testing protocol to measure efficacy in air. Among existing spatial repellents, DEET is the most common active ingredient. This research focuses on application of sensor-based technologies to monitor the concentration levels of DEET under static conditions.

Metal oxide semiconductor sensors feature conductivity variance in response to absorption and desorption of volatile organic compounds. Advantages of these sensors include cost, versatility, and sensitivity. Metal oxide semiconductor sensors were chosen …

Using Intrinsic Properties Of Polyaniline To Sense Expression Of The Microrna Let-7, Jared N. Gloria

Honors Theses

MicroRNAs are approximately 22-nucleotide long RNA molecules that function through decay and translational repression of messenger RNA. The microRNA let-7 is found to play a role in maintaining the fate of differentiated cells in humans. Thus, expression level of this microRNA is a reliable biomarker of tumor cell phenotype. However, there are significant limitations in the current profiling techniques of microRNA. The current methods like northern blotting, microarrays, RT-PCR, or using locked nucleic acid (LNA) for in-situ hybridization are either laborious, semi-quantitative, or expensive. In this research we try to address this issue by developing a fast, specific, and inexpensive …

The Effect Of Acrylic Acid On Ring Formation In Polyacrylonitrile, Elisha Cade Willis

Honors Theses

The addition of comonomers into carbon fiber precursor, polyacrylonitrile (PAN), has shown to have effects on the extent of stabilization and thermal behavior.1 Acrylic Acid (AA) was added at varying initial apparent weight percent and added via semibatch reaction to copolymerize with acrylonitrile to form carbon fiber precursor. Accompanying batch reactions were synthesized for comparison. Degradation was found to be greater in the semibatch reactions although overall was comparable to the batch reactions. Differential scanning calorimetry (DSC) confirmed the addition of higher concentrations of AA into the reaction resulted in a less intense exotherm upon cyclization, along with a greater …

Alluvial Sedimentation Associated With Logging In Low Gradient Watersheds In Desoto National Forest, Mississippi, Andrew W. Simmons

Master's Theses

Forestry and related businesses are an important factor of Mississippi’s economy, contributing between $11 and $14 billion annually (Mississippi Forestry Commission, 2006). The timber industry is not only important in Mississippi but is an important sector of the economy throughout the Gulf Coast region. While providing positive economic benefits to the region, the forestry industry can also negatively affect soil properties, hillslope stability, and increase sedimentation rates in local streams and rivers. The aim of this research is to determine if forestry removal causes an increase of soil erosion and how it affects floodplain sedimentation in the low gradient watershed …

Fire And Fuels: Vegetation Change Over Time In The Zuni Mountains, New Mexico, Luke Wylie

Master's Theses

The Zuni Mountains are a region that has been dramatically changed by human interference. Anthropogenically, fire suppression practices have allowed a buildup of fuels and caused a change in the fire-adapted ponderosa pine ecosystem such that the new ecosystem now incorporates many fire-intolerant species. As a result, the low-severity fires that the ecosystem once depended on to regenerate the forest are much reduced, and these low-severity fires are now replaced by crown-level infernos that threaten the forest and nearby towns. In order to combat these effects, land managers are implementing fuel reduction practices and are striving to better understand the …

Synthesis And Application Of (R)-3-Methylpyrrolidine-3-Carboylic Acid, Shelby D. Dickerson

Honors Theses

L-Proline is an amino acid widely used in pharmaceutical and biotechnological research due to its catalytic activity and biological relevance. L-Proline has been recognized and utilized as an organocatalyst, which allows cleaner, more sustainable reactions. However, one issue with L-proline is its low solubility in organic systems, limiting its reactivity and efficiency, especially when considering industrial research. Two reactions that utilize L-Proline are the Michael and Aldol but require 100 mol% of L-Proline and 30 mol% of L-Proline, respectively. This research will focus on the synthesis of an analogue of L-Proline utilizing inexpensive, commercially available reagents. A variety of organic …

Applications Of The Sierpiński Triangle To Musical Composition, Samuel C. Dent

Honors Theses

The present paper builds on the idea of composing music via fractals, specifically the Sierpiński Triangle and the Sierpiński Pedal Triangle. The resulting methods are intended to produce not just a series of random notes, but a series that we think pleases the ear. One method utilizes the iterative process of generating the Sierpiński Triangle and Sierpiński Pedal Triangle via matrix operations by applying this process to a geometric configuration of note names. This technique designs the largest components of the musical work first, then creates subsequent layers where each layer adds more detail.

A Chemical Sensor For Cyanide, Rachel E. Lambert

Honors Theses

The cyanide ion and its gaseous form, hydrogen cyanide, are extremely toxic. Cyanide impairs cellular respiration by inhibiting cytochrome c oxidase, an enzyme in the electron transport chain, leading to cell death.

In a previous study, we synthesized an optical sensor that detects cyanide selectively. The aim of this project is to increase the sensitivity of this sensor. This can be achieved by utilizing the unique spectroscopic properties of lanthanide ions.

The lanthanide metal (europium or terbium) was added to a coumarin-glycine chemodosimeter in a DMSO solvent system. The sensor was titrated with several monodentate analytes including, nitrate, octylamine, 1-pentanethiol, …

Momentum Transfer To A Simplified Wind Turbine Blade, Myer D. Milbrath

Honors Theses

This project looks into the potential of simplified simulations as a supplement to wind turbine blade designs. The idea is to take a two-dimensional representation of a wind turbine blade and attempt to use a fluid flow simulation to determine which "aspect ratio" is the most efficient in the transfer of momentum. This is then compared to the current requirements for wind turbine blades to judge how accurate the simulation was. It was found that an aspect ratio of 16.66 percent was most efficient, however when compared to the requirements for a wind turbine blade this ratio only falls into …

Investigation Of How Hydrogen Bonding Affects The Enantiomeric Excess Of Pig Liver Esterase Promoted Hydrolysis Of Pro-Chiral Substrates, Jacob E. Pruett

Honors Theses

Pig Liver Esterase is a cost effective enzyme for ester hydrolysis. In our group, it is vital for creating chiral molecules for the synthesis of unnatural amino acids of potential biological importance. It has been previously found that the enantiomeric excess (%ee) of the PLE hydrolysis reaction increases drastically with the addition of co-solvents that are able to both accept and donate hydrogen bonds. This research endeavors to see if substrates of enhanced hydrogen bonding ability also increase the stereoselectivity of PLE hydrolyses. Diester malonate was covalently linked with a furan ring in both the third and second position from …

Detection Of Acoustic Sources Using Time-Reversal Methods, Grant E. Tingstrom

Honors Theses

The goal of this research is to characterize the impact of using an equivalent-fluid method for a solid seabed on the use of time reversal procedures for detecting the origin location of an emitted sound. There are two different ways of modeling how sound propagates through water: modeling sound as a ray and modeling sound as a wave. It is easier to model the propagation of sound through water with a ray model; using a ray model allows for the collection of grazing angles with respect to the bottom. These will be important when determining bottom intensity loss of the …

Synthesis Of Acceptors For Use In Donor-Acceptor Copolymers And Characterization Of These Polymers, William D. Walker

Honors Theses

In this thesis, a selenium-derivatized acceptor was synthesized to examine the heavy atom effects of selenium on the position of the frontier molecular orbitals (HOMO/LUMO band gap) as opposed to sulfur in a donor-acceptor copolymer for use in light harvesting and detection applications. Over the course of this research, standard operating protocols for ultraviolet-visible (UV-Vis-NIR) and Fourier transform infrared (FT-IR) spectroscopies, as well as cyclic voltammetry (CV) characterization techniques were established. Once synthesized, the polymers were characterized through use of the established characterization protocols. The selenium-derivatized polymer exhibited a bathochromic shift compared to the sulfur analogue, with a solid-state absorption …